Rear glass defroster and defroster system and method for controlling the same

Abstract

A method for controlling a rear glass defroster for a vehicle upon start-up is presented. First, one or more factors are determined, which are selected from a temperature of an environment immediately outside the vehicle, a humidity of the environment, a dew point of the environment, a barometric pressure of the environment, a temperature of a rear glass of the vehicle, a temperature of an internal cabin of the vehicle and a sun load on the vehicle. Next, the one or more factors are compared to one or more corresponding predetermined thresholds or ranges that are indicative of conditions suitable for frost formation on a rear glass of the vehicle. Then, if the comparison indicates that the one or more factors meet the frost formation conditions, the rear glass defroster is activated. A vehicle rear-glass defrost system which uses the foregoing method is also presented.

What is claimed is: 
     
         1 . A method for controlling a rear glass defroster for a vehicle upon start-up, comprising:
 determining one or more factors selected from a temperature of an environment immediately outside the vehicle, a humidity of the environment, a dew point of the environment, a barometric pressure of the environment, a temperature of a rear glass of the vehicle, a temperature of an internal cabin of the vehicle and a sun load on the vehicle;   comparing the one or more factors to one or more corresponding predetermined thresholds or ranges that are indicative of conditions suitable for frost formation on a rear glass of the vehicle; and   if the comparison indicates that the one or more factors meet the frost formation conditions, then activating the rear glass defroster.   
     
     
         2 . The method of  claim 1 , further comprising:
 detecting a commanded start of the vehicle.   
     
     
         3 . The method of  claim 2 , wherein the detecting step is performed before the determining, comparing and activating steps. 
     
     
         4 . The method of  claim 3 , wherein if the commanded start is detected, then proceeding to the determining, comparing and activating steps. 
     
     
         5 . The method of  claim 1 , further comprising:
 establishing a location of the vehicle.   
     
     
         6 . The method of  claim 5 , wherein at least one of the establishing, determining and comparing steps is performed by a remote service that is in communication with the vehicle. 
     
     
         7 . The method of  claim 5 , wherein at least one of location-related information, factor-related information and comparison-related information is communicated between the vehicle and the remote service. 
     
     
         8 . The method of  claim 5 , wherein at least one of the establishing, determining and comparing steps is performed by a controller on-board the vehicle. 
     
     
         9 . The method of  claim 1 , further comprising:
 if the comparison indicates that the one or more factors meet the frost formation conditions, then setting a flag in a memory;   detecting a commanded start of the vehicle; and   if the flag is set and a commanded start of the vehicle is detected, then activating the rear glass defroster.   
     
     
         10 . The method of  claim 6 , wherein the remote service and the vehicle communicate with each other via one or more of a cellular signal, a satellite signal, a Wi-Fi signal, a Bluetooth signal, a radio signal and an internet signal. 
     
     
         11 . A method for controlling a rear glass defroster system for a vehicle upon start-up, wherein the system includes a rear glass, a rear glass defroster, one or more sensors, and a controller operatively connected with the defroster and the one or more sensors, the method comprising:
 determining, using the one or more sensors and/or a remote service that is in communication with the vehicle, one or more factors selected from a temperature of an environment immediately outside the vehicle, a humidity of the environment, a dew point of the environment, a barometric pressure of the environment, a temperature of the rear glass, a temperature of an internal cabin of the vehicle and a sun load on the vehicle;   comparing, using the controller and/or the remote service, the one or more factors to one or more corresponding predetermined thresholds or ranges that are indicative of conditions suitable for frost formation on the rear glass;   detecting a commanded start of the vehicle; and   if the comparison indicates that the one or more factors meet the frost formation conditions and a commanded start of the vehicle is detected, then activating the rear glass defroster.   
     
     
         12 . The method of  claim 11 , wherein the detecting step is performed before the determining, comparing and activating steps. 
     
     
         13 . The method of  claim 12 , wherein if the commanded start is detected, then proceeding to the determining, comparing and activating steps. 
     
     
         14 . The method of  claim 11 , further comprising:
 establishing a location of the vehicle.   
     
     
         15 . The method of  claim 14 , wherein at least one of location-related information, factor-related information and comparison-related information is communicated between the vehicle and the remote service. 
     
     
         16 . The method of  claim 11 , further comprising:
 if the comparison indicates that the one or more factors meet the frost formation conditions, then setting a flag in a memory associated with the controller; and   if the flag is set and a commanded start of the vehicle is detected, then activating the rear glass defroster.   
     
     
         17 . The method of  claim 11 , wherein the remote service and the vehicle communicate with each other via one or more of a cellular signal, a satellite signal, a Wi-Fi signal, a Bluetooth signal, a radio signal and an internet signal. 
     
     
         18 . A rear-glass defrost system for a vehicle, comprising:
 a rear glass;   a rear glass defroster for defrosting the rear glass;   one or more sensors configured to sense one or more factors selected from a temperature of an environment immediately outside the vehicle, a humidity of the environment, a dew point of the environment, a barometric pressure of the environment, a temperature of the rear glass, a temperature of an internal cabin of the vehicle and a sun load on the vehicle; and   a controller operatively connected with the defroster and the one or more sensors, the controller being configured to:
 determine the one or more factors using the one or more sensors and/or a remote service that is in communication with the vehicle; 
 compare the one or more factors to one or more corresponding predetermined thresholds or ranges that are indicative of conditions suitable for frost formation on a rear glass of the vehicle; and 
 if the comparison indicates that the one or more factors meet the frost formation conditions, then activate the rear glass defroster. 
   
     
     
         19 . The rear-glass defrost system of  claim 18 , wherein the controller is further configured to:
 detect a commanded start of the vehicle; and   if the comparison indicates that the one or more factors meet the frost formation conditions and a commanded start of the vehicle is detected, then activate the rear glass defroster.   
     
     
         20 . The rear-glass defrost system of  claim 18 , wherein the controller is further configured to:
 establish a location of the vehicle using the remote service.